2. DNA Replication (Sect 11.3) Objectives: Describe the structure and function of DNA and its role in the process of DNA replication.

4. Each strand of the double helix acts as a template due to complimentary base pairing. What is a template? The process of copying the DNA molecule is called DNA replication. The Template Mechanism

6. 1)The two strands of the double helix separate. 2)Free nucleotides line up one at a time across from the template strand. 3)Complimentary base-pairing dictates how the nucleotides line up. 4)Enzymes called DNA polymerases link the nucleotides together. DNA Replication

7. The process of copying DNA Sequence of bases on 2 strands complementary 1.Helicase breaks H-bonds & untwist Double Helix 2.DNA Polymerase pairs free nucleo. to open bases. 3.Occurs simultaneously @ many pts. along strand of DNA. 4.2 identical strands. The process of copying DNA Sequence of bases on 2 strands complementary 1.Helicase breaks H-bonds & untwist Double Helix 2.DNA Polymerase pairs free nucleo. to open bases. 3.Occurs simultaneously @ many pts. along strand of DNA. 4.2 identical strands.

8. DNA copy = Parent DNA + New DNA strand. Parent strand acts as a template for the new strand. DNA Synthesis

9. 1. What do the yellow strands of DNA represent? Transparency 11A-3 new DNA strands

10. Transparency 11A-4 2. What will the two daughter DNA molecules consist of? Each consists of one original (parent) strand and one new strand.

11. Original DNA Original DNA Strand Free Nucleotides New DNA molecule New DNA Strand New DNA molecule DNA Replication

12. DNA Replication Video

13. DNA Replication Real-Time Animation www.dnai.org

14. The existing strands of DNA serve as a template during replication. DNA Replication: A Review Because of complimentary base pairing, DNA can replicate itself with great accuracy. During replication, the DNA strand separates and nucleotides pair with their complimentary bases. DNA polymerases then bond the paired nucleotides.

15. Question 1 Why is DNA replication important to cell division? Answer Without DNA replication, new cells would have only half the DNA of their parents. Species could not survive and individuals could not grow or reproduce successfully.

16. Question 2 What serves as the template for the production of new DNA molecules? Answer The existing DNA strands.

17. Question 3 Which of the following are instrumental in bonding together the nucleotides of the new strand? D. DNA polymerase C. nucleotides B. purines A. catalase The answer is D.

18. DNA Replication (Sect 11.3) Objectives: Describe the structure and function of DNA and its role in the process of DNA replication.